how can I determine intended recipients using the OssClient.GetPackage(new PackageId(packageId));

I'm looking at switching from using the http client to using the sdk but I am running into diffences in the reponse object. The api returns a roles collection with a number of signers objects. the signers have a signer type, for ex.  "signerType": "ACCOUNT_SENDER",  or "signerType": "EXTERNAL_SIGNER", or "signerType": "EXTERNAL_SENDER", but there is an an additional property on the role which is either "type": "SIGNER", or "type": "SENDER",

When using the http client via the api, I could use the role type,  to determine the signers that I could use to get the intended recipients. 

However, when switching to the SDK, the role is not available, I can only see the signers array directly, and the response object returned from OssClient.GetPackage is missing that role type that distinguishes a signer from a sender. I'm not sure if I can use the signer_Type because that refers to the user type, and not the role in this current document package. I ran into an issue where another account was also a sender in the tenant, and in that case, that type returns the value "EXTERNAL_SENDER",

I'm also not sure if it's safe to use every item in the signers array that is NOT the "signerType": "ACCOUNT_SENDER",  because what if an account sender also wants to include themselves as a recipient for self signing.

Is there a recommended work around I can use here with just using the sdk?

Thanks